[15a-K501-1~4] 22.1 Joint Session M "Phonon Engineering"

11:00 AM - 11:15 AM JST(2:00 AM - 2:15 AM UTC)

[15a-K501-4] Impurity Dependence of Phonon Branches Connected with Thermal Insulation in a Heusler Alloy System Fe₂VAl

〇Satoshi Tsutsui^1,2, Koji Kimura³, Hidetoshi Miyazaki³, Yoichi Nishino³, Koichi Hayashi³ (1.JASRI, 2.Ibaraki Univ., 3.Nagoya Inst. Tech.)

Keywords:

thermoelectric material,lattice thermal conductivity,phonon dispersion relation

Heusler alloy Fe₂VAl is a mother compound for thermoelectric materials, which consists of ubiquitous elements. Replacement of V with Ti or Ta in Fe₂VAl makes its thermal insulation improved. We successfully grew the Ti- or Ta-doped single-crystalline Fe₂VAl samples. We have conducted inelastic X-ray scattering of the Ti- or Ta-doped single-crystalline Fe₂VAl samples to reveal the thermal insulation mechanism of Ti- or Ta-doped Fe₂VAl. The phonon dispersion relations obtained by inelastic X-ray scattering are different between Ti- and Ta-doped samples. These results demonstrate thermal insulation mechanism depends on doped impurities.